Tool for disassembling and reassembling brake heads and pistons



arch H, 1941. M. W. BUTCHER WM TOOL FOR DISASSEMBLING AND REASSEMBLINGBRAKE HEADS AND PISTONS 1 Filed July 15, 1940 2 Sheets-Sheet l 13% M.Emu-mm 2 4319 TOOL FOR DISASSEMBLING AND REASSEMBLING- BRAKE HEADS ANDPISTONS Filed July 15, 1940 2 Sheets-Sheet 2 Patented Mar. 11, 1941UNITED STATES ample PATENT OFFICE TOOL FOR DISASSEMBLING AND REAS- 8Claims.

My invention provides a highly efficient tool especially adapted for usein disassembling and reassembling brake heads andpistons. The improvedtool, while capable of more extended use, has been especially designedand particularly adapted for manipulating the non-pressure heads andpistons of brake mechanism of the type generally known to the trade asA-B brake head and piston which form portions of the New York air brakeand the Westinghouse air brake systerns.

The improved tool, which is in the nature of a power-actuated machine,is illustrated in the accompanying drawings wherein like charactersindicate like parts throughout the several views.

Referring to the drawings:

Fig. 1 is a front elevation with some parts broken away showing theimproved tool and a brake cylinder and piston assembly of the characterabove indicated held in position by the tool and showing thenon-pressure head set with the piston projecting upward therefrom;

Fig. 2 is a view corresponding to Fig. 1 but illustrating a differentposition of the non-pressure head and piston;

Fig. 3 is a front elevation with some parts in section but with the tooladjusted to hold the brake piston withdrawn from the non-pressure head;

Fig. 4 is a fragmentary plan view with parts broken away and with thebrake assembly elements removed;

Fig. 5 is a fragmentary view in side elevation of the parts shown inFig. 4;

Fig. 6 is a horizontal section taken on the line (i--6 of Fig. l; and

Fig. '7 is a side elevation showing in detail the aligning head used inconnection with or as a part of the improved tool.

Before describing the structure of the improved tool, the non-pressurehead and piston of the said A-B brake motor mechanism will be brieflynoted. In the drawings the non-pressure head is indicated by thecharacter a, and the piston head by the ch aracter b. The non-pressurehead a is shown as a truncated conical shell having an out-turnedmarginal flange o--] and a contracted neck a--2, which 1atter is groovedto form a seat for a removable packing a--3 that is normally held inplace by a retaining ring a4 rigidly but detachably secured by machinescrews a-5, or the like. The piston head 1) is formed with a stem b-iwhich, as shown, is hollow and is surrounded by a coiled spring b--2which, when the elements of the brake head are assembled,

will be compressed between the piston head and the contracted end of thenon-pressure head a. On the end of the piston stem bl is a stop collarb3 rigidly but detachably held on said stem by set screws b4, or thelike. The piston head head b in practice, of course, works in thecylinder of a brake motor, not shown, but the operation of which is wellunderstood by those familiar with brake mechanism.

The piston head b is shown as provided with the customary snap-onpacking or cover b-5 and swab packing bfi, which elements arereplaceable and require frequent replacement or repair. The head a, asshown, is provided with the customary strainer-equipped air vent a--6.

The tool or device proper in its preferred form involves a pair oflaterally spaced parallel upright guide posts Ill, which, at their lowerends, are securely anchored to a floor or base support ll. Rigidlysecured .to the upper ends of these posts I0 is an anchoring segment I2that is U-shaped in cross section with its opening inward and with itsends extended preferably through a little more than 180. anchoringsegment can be rigidly secured to the posts in various Ways but ispreferably electrically welded thereto. Near their lower ends the postsI!) are rigidly connected by a cross member l3 to the intermediateportion of which is rigidly secured a cylinder M that depends therefromand, as shown, is extended through the floor I I to a lower elevation.Both the posts I0 and the cross member 13 are preferably tubular, andthe posts are provided with smooth exteriors to afford guides for acrosshead that affords a lifting member or elevator. This crosshead, asshown, is made up of a horizontal member l5 provided at its ends withupright sleeves [6 that slide freely on the posts Ill.

Working in the cylinder 14 is a piston head H, the rod [8 of which worksfreely and loosely through a cap IS on the upper end of the cylinder sothat atmospheric pressure will be effective in the cylinder above thepiston head. The axis of the piston rod I8 is coincident with the axisof the arc of the anchoring segment i2 and the upper end of said rod isconnected to the intermediate portion of the cross bar or member [5 ofthe crosshead. Centering or aligning fingers r 26 are attached to theupper ends of the sleeves i6 and operate in a manner hereinafter to benoted. To lock or secure the non-pressure head a in either of thepositions shown in Figs. 1 and 2, its flange a--l will be inserted inthe channel of The said the anchoring segment l2 and will be lockedthereto by pins 2| inserted through coincident perforations in theflanges of said segment and in the flange 11-1 of said head a. The pins2| are shown as attached to the anchoring segment l2 by means of chainsor other flexible connections 22 which prevent the pins from beingmisplaced or lost.

The cylinder [4 and piston I! afford an air motor for applying power toraise the crosshead and to convey the motive fluid, air or water, to thelower end of said cylinder below said piston and supply pipe 23 is.extended from a suitable source to the lower portion of said cylinder.In the pipe 23 is a three-way valve 24, which when set as showndiagrammatically in Fig. 1, will vent the lower end of the cylinder andpermit the piston and cross-head to lower under the action of gravity.When the motive fluid is introduced into the lower end of the cylinderunder pressure, the crosshead, of course, and the load carried thereby,will be raised.

When the non-pressure head a and piston b are applied and held by thetool, as shown in Fig. 1, the piston head b will be projected andexposed where it can be readily worked upon for the re placement orrepair of the above noted packing elements b5 and b -6, and the interiorof the non-pressure head a will be exposed so that it can be readilycleaned if required.

When the non-pressure head a and piston b are turned upside down or asshown by full lines in Fig. 2, and the head a is then secured in theanchoring segment as shown in Fig. 2, the piston head will then restupon or just above the cross member l5 of the crosshead. Then when thecrosshead is raised, the piston will be moved upward substantially asshown by dotted lines in Fig. 2, against the tension of spring bZ, andthe upper end of piston rod will be projected so that its stop ring b3can be readily removed. When the piston is thus raised, as shown bydotted lines in Fig. 2, the packing clamping ring a4 can be readilyremoved, thereby affording access to the packing (1-3 for the removal,replacement or repair thereof.

I have found in practice that after the operations just described havebeen performed, the packing a3 .Would be frictionally raised out of itsseat by giving the crosshead and the piston structure a little furtheradditional upward movement.

Preferably the next operation would be to lower the crosshead Ito theextreme position shown in Fig. 3, so as to draw the piston stem or rodbl completely out of the non-pressure head a, leaving the latterseparated. While the non-pressure head is removed, it can be internallyand externally cleaned and its air vent a--6 and its strainer can alsobe conveniently cleaned or replaced. While the non-pressure head isremoved, spring b2 can be readily removed and the said spring and thepiston stem can be cleaned. After the non-pressure head has beenreplaced, as shown in Fig. 3, the crosshead and the piston structurewill be raised so as to project the stem 22-! upward through the saidhead. To facilitate the entrance of the piston stem through the hub orcontracted portion of the non-pressure head a, I have found itconvenient to apply a contracted aligning cap 25 temporarily to theupper end of said piston stern. After the piston stem has been forcedupward through the nonpressure head, cap 25 will be removed and thepacking a3 can be replaced in its seat and around the piston stem. Thenby a downward movement of the piston and stem, this packing thus appliedwill be frictionally drawn to the bottom of its seat and then theretaining ring a-4 should be reapplied.

The next step would be to reapply the stop ring b3 thereby againconnecting the piston and non-pressure head structures in cooperativerelation ready for reapplication to the brake motor. It is important tonote that the pins 2| and the holes therefor in the anchoring segment l2and in the flange of the non-pressure head are diametrically opposite sothat they will enter coincident holes regardless of whether the pressurehead is turned upward as shown in Figs. 2 and 3 or downward as shown inFig. 1.

Attention is also called to the fact that under upward movement of thecrosshead, the aligning or centering fingers 20 will engage the somewhattapered lower portion of the piston head and initially center the samein respect to the head a.

In Figs. 4 and 5 the offset portion of the anchoring segment [2 is shownas rested on a bracket 2610f a table or adjacent support 21.

It may be noted that as a minor feature the guide posts or columns I0are diametrically spaced in respect to the anchoring segment, and thatthe lock pins 2| which are also diametrically spaced, when inserted,will project downward into the posts.

What I claim is:

1. In a device of the kind described, spaced guide columns, a crossheadslidable on said columns, power means for reciprocating said crosshead,an internally grooved anchoring segment secured on the upper ends ofsaid columns and adapted to receive the flange of a brake head such asdescribed regardless of which side up said head is turned, and to holdsaid brake head aligned with the axis of a brake piston seated on saidcrosshead.

2. In a device of the kind described, spaced guide columns, a crossheadslidable on said columns, power means for reciprocatnig said crosshead,an internally grooved anchoring segment secured on the upper ends ofsaid columns and adapted to receive the flange of a brake head such asdescribed regardless of which side up said head is turned, and to holdsaid brake head aligned with the axis of a brake piston seated on saidcrosshead, said anchoring segment being extended through aproximatelyand having diametric pin holes, and in combination with pins insertablethrough said pin holes and through holes in the flange of said brakehead.

3. The structure defined in claim 1 in which said crosshead has uprightsleeves slidable on said columns and has a transverse connecting barserving as a support for a piston axially aligned with said anchoringsegment and brake head held thereby.

4. The structure defined in claim 2 in which the pin holes in saidanchoring segment are axially aligned with said columns so that theinserted pins will project downward into said columns.

5. The structure defined in claim 1 in which said crosshead has uprightsleeevs slidable on said columns and has a-transverse connecting barserving as a support for a piston axially aligned with said anchoringsegment and brake head held thereby, said sleeves at their upperportions having inwardly projecting aligning finers located above thecross bar of said crosshead.

6. The structure defined in claim 1 in which the power means for movingsaid crosshead includes an anchored cylinder having a movable piston rodintermediately connected to said crosshead.

7. The structure defined in claim 1 in which said crosshead has uprightsleeves slidable on said columns and has a transverse connecting barserving as a support for a piston axially 10 aligned with said anchoringsegment and brake

